Automatic musical instrument



Patented Mar. 14, 1922.

j e ntor;

Russe UNITED STATES PATENT OFFICE.

GUY MANLY RUSSELL, OF ROCHESTER, NEW YORK, ASSIGNOR TO AMERICAN PIANO 1 COMPANY, OF NEW YORK, N. Y., A. CORPORATION OF NEW JERSEY.

AUTOMATIC MUSICAL INSTRUMENT.

Specification of Letters yatent. Patented Mar. 14 1922 Application filed December 20, 1913, Serial No..807,815.-1 Renewed April 4, 1921. Serial No. 458,431.

To clin c/tom it may concern:

Be it known that I, GUXMANLY RUSSELL, acitizen of the United States, and a resi- Hdent of Rochester, county of Monroe, and

ings, is a specification, like characters on the drawings representinglike parts.

-.This invention relates to automatic means for playing 'musical instruments such, for instance, as pianosyand pertains more particularly to means for governing and varying tone intensities. p

. Among other objects, the invention is intended to provide apparatus capable of producing a great variety of variations in intensity of playing, such apparatus comprising preferably, though not essentially, a combination of means for producing crescendo and decrescendo effects and also in stituting various defined grades or steps of playing intensity. ,For these purposes the invention may be embodied in apparatus which is very simple and reliable in operation. l a i For illustration, theaccompanying drawing shows one practicable embodiment of the invention employing suitable pneumatically governed devices in cooperation witha piano action;-but-, as will appear to those skilled in the art, the invention is susceptible of embodiment in various constructions and organizations other than that par ticularly shown and described herein. It will appear likewise that it is not indispensable that all the features of the invention be used conjointly, since their respective substantial advantages may accrue from their separate application in any practicable manner to a suitable playing instrument.

In the drawings:

The figure is a diagrammatic representa-' tion of atypical piano action,- with operating and governing means exemplifying the application and utility of the invention;

Referring to the drawing, a typical piano action shown in its normal position of rest comprises. a key-controlled sticker B to act upon a wip pcnI, hammer C. damper E, string, D and other parts which may be those well known in the art. To operate the action pneumatically, a motor pneumatic F is provided, having a sticker H to act upon the wippen I A wind trunk 7 leads to the wind chest forthe motor pneumatics, each of which has a secondary valve 8 controlled by 'a primary valve 9 operated from a tracker-board G through a duct 10, in the usual manner,

The trunk v7 communicates. with a regulated exhaust chest 12, which maybe of any practicable construction. A high exhaust chest 14, arranged for communication with the chest 12, may be connected by a trunk 15 with any source of pneumatic exhaust, such as feeder bellows of any practicable type.

F or the purpose of explaining the general character of this invention, and to exemplify one practicable manner of governing tone intensities, I have selected the ap paratus of the drawings in which the striking pneumatics F are caused to operate by the regulated exhaust in'the chest 12. this regulated exhaust being varied, in order to vary the operation of'the striking pneumatics, by subjecting it more or less to the influence of the high exhaust in the chest 14. For these specific purposes I have provided, between the high exhaust chest lei and the regulated exhaust chest 1.2a port 3(), controlled by a throttle valve 31.

This valve 31 may be operated by a variety of diiferent means. In this specific apparatus, the stem 32 of the valve 31 is connected to a movable board 33 of a bellows apparatus presently described, said board being hinged at 33",

Beneath the board 33 are three pouches 34, 35, 36, having their upper boards secured to the vcommon movable board 38 and their lower boards secured to a fixed plate 36 as shown. The pouches may be made adjustable toward and from the hinge: 33, to vary their leverages in any practicable manner as by having their upper and lower boards secured by screw and slot connections to the movable board 33 and lower supporting plate respectively Another pouch 37 has its lower board s cured to the movable board 33 and its upper boardto a stationary plate 88. A. condition of partial exhaust is maintained at all times in the pouch 37 as presently described. The degree of exhaust in the pouch 37 may be varied; but for the present this capacity may be neglected and the pressure within the pouch acting upon the board may be considered uniform.

Thus, the pressure in the pouch 37 being always less than atmospheric pressure, said pouch in effect exerts continuously an upward pull upon the board 37, contributing to control the valve 31. I

' Ducts 40, 41 and 42 enter respectively th pouches. 34, 35 and 36. Each duct is controlled (as hereinafter explained) so as to admit to its pouch either atmospheric pres sure, or regulated pressure from the chest 12; and the regulated pressure may be admitted to any one or more or all of the pouches, while atmospheric pressure will be I present in those pouches, if any, which do not contain regulated pressure. Whenever regulated pressure (which is always less than atmospheric pressure) is present in one or more of the pouches 34, and 36, the effect thereof is to produce a downward pull upon the board33 (i. e. the differential between atmospheric pressure on the top of the board 33 and the lesser regulated pressure in one or more of the pouches); and

" this resultant downward pull opposes the upward pull by the pouch 37, the two contributing to control the valve 31. High exhaust in thechest' 1'4 exerts some downward pressure upon the area of the valve 31 it self; and the regulated pressure in the chest 12 exerts some upward pressure upon the area of the valve. The regulated pressure being greater, it predominates and the resultant upon the valve itself is an upward pressure which combines with the resultant of the pressures in the several pouches to complete the control of the valve 31.

Thus, the valve 31 is controlled by the differential between the upwardly acting pull of the pouch 37 and the pressure in the chest 12 on the valve itself, and the downwardly acting pulls of such of the pouches 34, 35, 36, as contain regulated pressure plus the downward pressure of the highly rarefied air in the chest 14 on the top of the valve 31. I The areas of the various pouches, and their leverages in respect to the board 33, are such that these opposed upwardly and downwardly acting pressures so control the valve 31 as to tend to hold it in a balanced condition. For example, if regulated pressure be present in all three of the pouches 34, 35 and 36, the downward pull of these pouches. upon the board 33 is at its maximum and tends to close the valve 31 and minimize the opening between the chests 12 and 14. Such closing of the valve 31 and restriction of communication between the chests, tends to reduce the suction in the regulated pressure-chest 12, andv this reduction in suction is immediately communi cated to the pouches 34, 35 and 36, to reduce the downward pull thereby. In this mannor the tendency to close the valve 31 is checked and it is closed to such an extent only as will produce a balance between the aforesaid downwardly acting forces and the upwardly acting forces.

If, under these circumstances, atmos here be admitted, for instance, to the pouc 36, the aggregate downward pull upon the board 33'is relaxed to some extent tending to permit 'the upwardly acting forces to open the valve 31 correspondingly. If the valve be thus opened, the communication between the chest 12 and 14 is thereby enlarged so that the degree of exhaust of the regulated pressure is increased and thereby the downward pull by the pouches 34 anlb35 is'correspondingly increased until the downwardly and upwardly acting forces are again brought to a balance.

If atmosphere be admitted to all the pouches34, 35 and 36 the downward pull by said pouches upon the board 33 will be minimized and the upwardly acting forces referred to will so largely predominate that the valve 31 will be open to enlarge communication between the chests 12 and 14'to the maximum.

It will be evident to those skilled in the art, that the more of the pouches 34, 35 and 36 which contain regulated pressure, the greater will be the aggregate downward pull by said pouches and the greater will be the tendency to constrict communication be tween the chest 12 and 14 by the valve 31. In other-words, the more of the pouches 34, 35' and 36 which contain regulated pressure, the less is regulated pressure subjected to the influence of high exhaust and the less will be the intensity of sounded tones. Accordingly, the general operation of the pouches described may be conveniently summarized thus :admitt ing regulated pressure to one or more pouches diminishes intensity; admitting atmospheric pressure to one or more pouches increases intensity.

In the operation of the specific illustrative apparatus the board 33 and valve 31 are constantly under the control of opposed forces tending always to balance each other and hold'the valve 3.1, as it were, in suspension between them; that is to say, the specific apparatus tends constantly to establish a balancingequation between the opposed forces acting upon the valve 31. Such move ment of the valve 31 as may occur when that balancing equation is disturbed, takes place practically instantaneously so that a new balancing equation appropriate to the newly initiated conditions is immediately set up.

The actual variation of regulated pressure may result from a number of causes. or a combination of causes, such that the valve 31 may or may not be moved to assist in a re-establishment of the pressure equation above referred to, whichholds the valve in balance, all as will be understood by those skilled in the art.

,Any practicable means may be employed to control theducts' 410, -11 and 42 to introduce atmosphere and regulated pressure alternatively to one or more of the pouches 3 1, 35 and 36. For this purpose I prefer to use the valve mechanisms described in certain application of Charles F. Stoddard, copending herewith. Any suitable mechanisms, however, preferably controlled from the tracker, may be" employed as will be understood by those skilled in the art and they are represented merely diagrammatically in the drawings at 50, 50 and 50. Since these valve mechanisms, specifically, constitute no part of the present invention, further description thereof is deemed unnecessary;

As will be understood this present invention is more particularly concerned with the utilization 'of the regulating means comprising the pouches 341, 35 and 36, and addi tional elements 'of the regulating apparatus, in the production of changes of playing intensities for instance, in the production of crescendo and diminuendo effects. For the present, therefore, in'the following description, the pouches 34,35, and 36, may be considered as performing merely a part of the regulating function to maintain uniformity of playing intensities whether one or many tones be sounded, and the capacity for changing the pneumatic condition in said pouches selectively from regulated pressure to atmosphere and vice versa, may be temporarily disregarded.

It has been'stated he'reinbefore that the pouch 37 is maintained constantly in a condition of partial'exhaust. The means by which a normal minimum degree of exhaust may beinaintained in the pouch 37 will be first described. A duct 100 connects the interior of the pouch 37 with a valve chest 101 containing a throttle valve 102. The valve 102 is located in the chest having a duct 103 to high exhaust, adjacent the needle end of the valve, and a second duct 1041, also to high exhaust, adjacent a transverse circumferential passage 105 of the valve, which controls communication between the duct 10% and a duct 106. A duct 107-connects the chamber- 101 with a duct 1'08 adjacent a second circumferential pa sage 109 of valve 102 which passage controls communicationbetween said duct 10S and a duct 109 leading through the stag tionary board 110 of a valve pneumatic 111,

Operatively connected with the pouch 37 as by aduct 115 is an'equaliaer 116 preferably provided with a bleeder vent 117 to atmosphere. Th'e'equalizer pneumatic 116 isemployed to provide a suilicient elastic regulating volume of air to render the pouch 37 sensitive and readily responsive to such movement of the board 33 as takes place in the operation of the valve 31; and such function of the equalizer 116 pertains principally, if not entirely, to the variation of intensities by changing from atmosphere to regulated pressure in the pouches 34, 35 and 36. Therefore, the following description may well disregard the presence of the equalizer 116 except to state that the preferred bleeder vent 117 to atmosphere contributes to maintain desired minimum degree of exhaust in the pouch 37 as more fully described hereinafter.

Returning now to the valve regulating pneumatic 111, the interior thereof connects the duct 109 with a duct 120 having, in the specific apparatus, two branches 121 and 122. The branch 121 is restricted by adjustable vents 123 and 1241; and the branch 122 is restricted by an adjustable vent 125. As the parts standin the position shown in the drawing, atmosphere is admitted through the valve chamber 126 to both the branches 121 and 122 and bleeds past the vents 123, 121 and 125, through the duct 120, pneumatic 111, duct 109, and past the circumferential passage 109 of the throttle valve 102 and into the ducts 108 and 107. The atmosphere thus bleeding in is exhausted through the passage 106, past the circumferential passage 105 in the valve and through the duct 104.; and also through the valve chamher 101 past the needle end of the valve 102 and through the duct 103, the ducts 103 and 10 91: communicating as shown with a duct 130 leading to any convenient source of exhaust, preferably high exhaust.

With the arrangement thus far described, there is provid d a pneumatic circuit bening at vents 123, 12 1 and 125 and extendthrough the penumatic 111 and past the alve passages of the valve 102, and thence to the source of exhaust through the duct 130, this circuit including also the pouch 37. Atmosphere is also admitted to this circuit in some degree through the vent 117 in the equalizer 116, but this being constant and of constant effect in the apparatus, it may be left without further descrip..ion.

Because exhaust is constantly acting upon the described pneumatic circuit, the pressure in said circuit is always less than'atmi'isphere and therefore some degree of exhaust is always maintained in the pouch 37. Because atmosphere is permitted to bleed into said circuit, the degree of exhaust therein is less than high exhaust the duct 130 and therefore the de rce of exhaust in the pouch 37 i the conditions shown in the drawing, less than high exhaust.

The vents 123. 124 and 125 are so adjusted in the specific apparatus that they permit enough atmosphere to bleed into the described pneumatic circuit to reduce the degree of exhaust therein to a certain desired minimum which is maintained constant under normal conditions by the operation of the valve 102 and other auxiliary means, as presently more fully described.

Thus, the normal pneumatic circuit between the vents 123, 124 and 125 and high exhaust, and including the penumatic 111 and the pouch 37, performs in effect the functions of a regulator spring acting in 0p position to the regulator pouches 34, 35 and 36; but this pneumatic circuit, which may be called for convenience a pneumatic regulator spring, possesses very substantial advantages over the mechanical tension spring generally employed with regulators heretofore known in the art. For instance, by employing the so-called pneumatic spring, regulating mechanism may be used to maintain the pull by the pneumatic spring to all intents and purposes perfectly uniform and without those variations in tension to which a mechanical spring is subject. This permits the predetermination of changes in intensity to be made with substantially greater refinement because of the reliably uniform character of the pneumatic spring pull which largely determines the behavior of the regulator. Also, the so-called pneumatic spring is substantially more sensitive and responsive than would be a mechanical spring, in that the latter always presents some degree of inertia which must be overcome in regulating the expression-varying operations, whereas the extremely minute inertia of the elastic volume of rarefied air in the pneumatic spring circuit is altogether ne ligible.

The manner in which the pull by the pneumatic regulator spring is maintained normally uniform, will be next described.

If, for example, regulated tension in the chest 12 be subjected to a sudden influx of atmosphere (as when a number of tones are sounded simultaneously by the playing pneumatics), the degree of exhaust of the regulated pressure is suddenly decreased and this decrease is communicated temporarily to the regulator pouches 34, 35 and 36, and the downward pulls exerted thereby may be substantially relaxed permit-ting the board 33 and the valve 31 to be lifted and the valve opened in the process of regulating or restoring regulated pressure. This lifting of the board 33 permits some collapse of the pouch 37 which reduces the interior volume of the pouch and thereby reduces suddenly the degree of exhaust throughout the penumatict spring circuit. This reduction in the degree of exhaust in the pneumatic circuit, being communicated to the interior of the pneumatic 111, permits the same to be expanded somewhat by its spring 111 and this expansion is communicated in turn to the ralve 102 which is secured to a finger 131 upon the movable board of the pneumatic 111. Thus, the temporary expansion of the pneumatic 111,because of the reduction of the degree of exhaust in the pneumatic circuit,has the effect of moving the valve 102 downwardly from the position shown in the drawing, whereby the opening between the exhaust duct 104 and the duct 106 is increased, permitting a greater flow of rarefied air therethrough to compensate immediately for the original diminution in exhaust which inaugurated the readjustment; and thus the desired minimum degree of exhaust throughout the pneumatic spring circuit is automatically restored.

For further illustration, assume that regulated pressure be admitted to the pouch 36 alone, atmosphere being in the other two pouches 34 and 35; and, the opening past the valve 31 being then nearly at its maximum, regulated pressure be suddenly introduced also into the two pouches 34 and 35. This will inaugurate a sudden downward pull upon the board 33 which may materially expand the pneumatic spring pouch 37, thereby suddenly increasin the interior volume of the pouch 37 and a so increasing the degree of exhaust in the pneumatic spring circuit. This increase in .exhaust being communicated through the circuit to the pneumatic 111, the latter is collapsed somewhat, thereby lifting the valve 102 and further restricting the opening between the suction duct 104 and the duct 106, cutting off suction to some extent from the circuit. and reducing the degree of exhaust in the circuit to the desired minimum.

As will appear to those skilled in the art, such movements of the board 33 as occur in the performance of regulating or expression-varying functions, produce corresponding movements (perhaps of less extent) of the movable board of the pneumatic 111, which movements, transmitted to the valve 102, cause said valve to perform itself a regulating function in respect of the pneu matic spring circuit, such that the degree of exhaust in said circuit is at all times uniform under the conditions illustrated in the drawing.

Those parts of the apparatus described above are effectual to maintain the pneumatic spring pull uniform within certain limits, but under some circumstances, which are likely to arise frequently in planking some compositions, it is preferred, for the purposes of the specific apparatus, to provide additional means supplementing the regulating ofiice of the valve 102 to compensate for such deficiencies as exist in .the operation of said valve. The additional means about to be described greatly increase the rapidity of restoration of the desired degree of exhaust in the pneumatic circuit, by

supplementing the action of the valve 102, and also prevent the possibility 01 any undesirable reduction (as by a too great movement of the valve 102) in the degree of exhaust in the pneumatic circuit. By thus enhancing'the sensitiveness and responsiveness of the pneumatic spring system, and safeguarding against an undesirable operation of the valve 102, the additional regulating instrumentalities contribute importantly to the extreme refinement of regulation desired in the highly developed types of automatic instruments to which this invention pertains.

For illustration, the accompanying drawings show a valve 135 hinged at 136 and connected by a finger 137 to the stem of the valve 102. hen in. closed position the valve 135 closes a port 138 of a channel 139 and also a second port 140 of a channel 141. The channel 139 communicates with a diaphragm chamber 142, the diaphragm ,{of which controls a valve 143 in the chamber 126. When the valve 1.35 opens the port 138 it thereby admits atmosphere to the channel 139, lifts the valve 143, shuts off atmosphere from the chamber 126 and places the same in communication with high exhaust in the chest 145. Atmosphere is thereby shut off from the channel 121 and high exhaust pressure is admitted thereto, past the vents 123 and 124 so that the principal source of atmosphere for the pneumatic spring circuit is cut off and is replaced by high exhaust pressure. Under these circumstances a new source opened into the pneumatic spring circuit past the restriction of the high exhaust pressure bleeds 123 and 124. Thus, whenever the valve 102 drops far enough (under circumstances presently described) to open the port 138, the ultimate result is to introduce a slow influx of suction to the pneumatic spring circuit to assist in restoring the degree of exhaust therein, the reduction in which permitted the pneumatic 111 to expand and move the valve 102 downwardly.

The duct 141 leads to a diaphragm chamber 150, the diaphragm of which controls a valve 152 which. in the position shown, admits atmosphere to the chamber 153. A duct 154 connects the chamber 153 with an other diaphragm chamber 154 having a disk valve 155 which normally closes a passage 156, which. together with a second passage 157, provides a hy-pass for the channel .121 around the vent 123.

The vents 1'23 and 124 arerelatively adj usted so that the vent 123 provides a materially smaller bleed than does the vent 124. Therefore, when air is exhausted from the pneumatic spring circuit through channel 121 past the valve 143 (the parts, with the exception of valve 143, being in the position shown) the smaller bleed past the vent 123 determines the speed of exhaust from the penumatic spring circuit; whereas if air is exhausted through the bypass 156157 and past the larger vent 124, the exhaust of air from the penumatic spring circuit will be substantially more rapid.

lVhen the valve 135 is moved far enough to open materially the ports 140, atmosphere is admitted thereto and to the diaphragm chamber 150, thereby closing the chamber 153 to atmosphere and opening it to high exhaust from the chest 145. This exhausts the duct 154 and diaphragm chamber 154 thereby withdrawing the valve 155 and open ing the by-pass 156, 157. It will be noted from the specific arrangement of the valve 135 and ports 138 and 140, that the port 140 is opened subsequently to the opening or the port 138. Therefore, when the by-pass 156, 157 is opened, the pneumatic spring circuit is exhausted through a double path leading to the chamber 126,i. e. past the vent 123 and also past the vent 124 and through the unrestricted by-pass 156, 157. Under these circumstances, the exhaust of air from the pneumatic spring circuit is much more rapid and the restoration of the desired degree of exhaust therein is accomplished much more quickly.

When the parts are in the positions shown in the drawing they have those adjustments appropriate to the normal maintainance of a minimum degree of exhaust in the pneumatic spring circuit. Under these circumstances the pneumatic 111 is partly collapsed away from its adjustable stop 111"; the valve passage 105 oi? the valve 102 is so located as to restrict somewhat the opening between the exhaust duct 104 and the opposite duct 106; and thevalve 135 is closed so as to leave the valves 143 and 152 in the positions shown. The finger 137 on the valve 135 is positioned beneath a collar adjustably secured upon the stem of the valve 102; and the adjustment 110 of said collar is such that when the valve 102 moves downwardly (upon a reduction in the degree of exhaust in the circuit. below the desired minimum) from the position shown, the port 138 will be opened to inaugurate 115 the described operation of cutting off atmosphere from the duct 121. and placing the same in coi'nmunication with exhaust thus drawing air slowly past the small bleed of the vent 1123 thereby supplementing the ad- 120 ditional withdrawal of air from the system past the valve passage 105 of the valve 102, which passage has been moved downwardly to increase the opening to the exhaust duct 104, by the downward movement of the 125 valve. This results in a practically instantaneous increase in the degree of exhaust in the pneumatic spring circuit, which increase is immediately communicated to the pneumatic 111, causing the same to collapse 130 slightly and to restore the parts to the positions shown in the drawing. It will be evident to those skilled in the art that this restoration of the desired conditions is great ly expedited by the slow cxhaustpast the slow bleed of the vent 123.

If the valve 102 moves downwardly far enough, not only to open the valve port 138 but also to open materially the port 140, then the restoration of desired conditions is caused to take place with maximum rapidity by the described operation of lifting the valve 152, exhausting from the diaphragm chamber 1541 and opening the bypass 156, 157 which creates a second path through which air may be exhausted from the pneumatic circuit past the large bleed of the vent 124. Thus the greater the movement of the valve 102 downwardly from the ideal adjust-merit indicated in the drawing, the more rapidly will the valve be returned and the more rapid will be the resumption of the desired minimum degree'of exhaust in the pneumatic spring circuit.

Thus it will. be observed that the valve 143 normally operates as a regulator valve to assist in maintaining a substantially uniform degree of exhaust within the pneumatic spring circuit. This normal operation of the valve 143 may, however, be varied as hereinafter explained. v 7

While the high perfection of refinementsecured by such means as that described above, is not required for the ordinary piano players, this invention is intended more particularly for use in connection with highly developed instruments used to reproduce the playing of great artists, the characteristics of whose performances are directly recorded, the record being employed in making special perforated music sheets capable of faithfully reproducing such performances. The intention being to reproduce as many as possible of the refinements in shadings of intensity by the manual playing of the artist. it is obvious that the greater refinement of operation of the reproducing apparatus. the greater the fidelity of the reproduction. In the solution of these problems of reproduction. the dependability of a imiform regulating pull, such as that secured by the pneumatic regulating spring apparatus above de scribed. with its own regulating valves to maintain and instantaneously restore uniformity of pull, is of the greatest value.

Thus in the operation of the described apparatus the functioning of the Various parts is readily observable in that the movements of the board 33, which is directly connected with the regulator valve 31, are accompanied by responsive movements of the movable board of the regulating valve pneumatic 111, and these as occasion requires are accompanied by responsive operations of the auxiliary regulating valves 143 and'152, all of these elements contributing their individual operations to the maintenance of the uniformity of pull by the pneumatic spring acting through the pouch 37 and, second, to the maintenance of uniformity of regulated pressure in the chest 12 at whatever level of intensity may be determined by the selection of pouches 3 1, 35 and 36 containing regulated pressure.

The highly refined regulating mechanism above descrlbed is susceptible of use not only in maintaining uniformity of playing intensities but also in varying playing intensities by varying the pull upon the main regulator board 33 by the pneumatic spring.

As will be understood by those skilled in the art, whenever either or both of the valves 1 13 and 152 was or were lifted to restore the valve 102 to the ideal position shown in the drawing, that restoration of the valve 102 at once closed the valve 135, permitting the diaphragm chambers 1 12 and 150 to be exhausted through the usual bleeds and thereby permitting the valves 143 and 152 to drop immediately to the positions shown. Thus the valves in the usual regulating action would be lifted only momentarily and then dropped. v This same regulating apparatus, however, may be availed of for producing excellent crescendo and diminuendo effects at different speeds, thereby producing a still further refinement in the playing of the instrument while retaining all of the important refinement in regulation.

If the valve 14.3 be held lifted, and air be exhausted for a substantial period past the small bleed of the vent 123, the degree of exhaust in the pneumatic spring regulating circuit and the, pouch 37 will be gradually increased during that period, and thereby the upward pull by the pouch 37 upon the valve 31 will be gradually increased so as to modify the regulation and produce a slow crescendo.

Similarly, if both the valves 143 and 152 be held lifted for a substantial period. thereby permitting air to be exhausted from the pneumatic spring regulating circuit along the double path including the by-pass 156, 157 and the larger bleed of the vent 12-1, then the degree of exhaust in the pneumatic spring circuit and the pouch 37 will be more rapidly increased, thcreliy rapidly increasing the pull by the pouch 37 upon the valve 31 and producing a rapid crescendo.

Following a slow crescendo operation by the lifting and upholding of: the valve 143 (the valve 152 remaining idle as shown) if the valve 143 be dropped, atmosphere will then be admitted to the chamber 126 to bleed into the pneumatic spring regulator circuit past the vent 123. This will gradually reduce the degree of exhaust in the pneumatic circuit, thereby gradually relaxing the pull of the pouch 37 upon the regulator Valve 31 and'producing a slow decrescendo. It is found that if the vent 123 be adjusted to produce the desired speed of flow when the degree of exhaust in the duct 120 is being increased, the capacity of the bleed with that adjustment is not suflicient to produce the desired results when'atmosphere is being admitted to the duct 120 past said vent 123. Therefore it is preferred to provide the auxiliary passage 122 restricted by the adjustable vent 125 through which atmosphere may bleed simultaneously with its bleed through the passage 121, and by adjusting the vent 125 the influx of atmosphere producing the decrescendo may be regulated to the proper speed. It being desired that exhaust shall not pass through the channel 122 for .regulating'purposes or in producing a crescendo, the mouth 160 of the channel 122 is'arranged to be closed by the valve 143 when the same is lifted to shut off atmosphere. i

If both. the valves 1 13 and 152 be lifted and upheld to produce a fast crescendo, and if then the valve 143 be dropped to the position shown (the valve 152 remaining upheld) then atmosphere admitted to the chamber 126 will be permitted to bleed rapidly into the pneumatic spring regulator circuit through a three-part path, i. e. the channel 122, the channel 121 past the vent 123, and the by-pass 156 and 157 ast the vent 124. This comparatively rapi influx of atmosphere will produce a rapid decrescendo.

During any crescendo operation the gradual increase in'the degree of exhaust in the a pneumatic spring regulator circuit has the effect of collapsing t e regulatorpneumatic 111 (the speed of collapse being slow or fast according as the valve 143 is lifted alone or together with the valve 152) and by the collapse of the pneumatic 111 the needle valve 102 is drawn upwardly the lower needle end thereof gradually increasing the opening'between the exhaust duct 103 and the valve chamber v101 thereby causing a progressively greater draft by exhaust upon the pneumatic spring circuit. In like manner, during a decrescendo at either of the speeds described, the pneumatic 111 expands gradually thereby moving the valve 102 downwardly so that its needle end diminishes the opening between the exhaustdu ct 103 and the valve chamber 101 and gradually diminishing the draft of exhaust on the pneumatic spring circuit.

'The above described operation of the pneumatic spring regulator circuit for producing crescendos and diminuendos, may be controlled by any practicable means, manually governed or otherwise, which will serve to govern appropriately the valves 14:3 and 152 in a manner similar to that of the ports 138, 140 and the valve 135. For illustration, the duct l39'(havi ng theport 138) may be connected by a duct 170 with a vent in the tracker bar to be opened by perforations in the music sheet to produce slow crescendos and to be closed to permit the ensuing slow decrescendos; and the duct 141 having the port 1 10 may be connected by a duct 171 to another tracker vent to be opened when the crescendos and diminuendos, or either, are or is desired to be made rapidly. Thus by merely connecting the appropriate parts of the regulator circuit to the tracker bar the regulator circuit may be made automatically to serve, in addition to its usual regulating functions, to produce crescendos and dimin uendos at different speeds.

The utilization of the regulator pouches 3 1, and 36 to produce changes in playing intensities by distinct increments or steps, as already described, and the variation in the pull of the pneumatic regulator spring to produce crescendo and diminuendo effects, may be combined to advantage. For example, the valve mechanisms 50, 50 and 50* may determine the starting point in the scale of intensities, of a crescendo or diminuendo, wherebythe same may be superposed as it were upon an already existing intensity regulation. Likewise, a' rapid crescendo may be superposed upon a slow crescendo by first opening the tracker duct 170 and thereafter, while it remains open, opening the duct 171; or, both said ducts 170 and 171 being opened, the slow crescendo may be superposed upon the rapid, by causing the vent 171 to be closed,'the vent 170 remaining open. In like manner, a fast diminuendo may be superposed upon an already existing slow diminuendo, or vice versa, as will appear to those skilled in the art.

The playing intensity may be increased by a sudden practically instantaneous step (utilizing the valve mechanisms 50, 50 and 50 superposed upon a crescendo which is in progress, thereby for exampleparticle larly emphasizing some note or notes in the crescendo. vSuch effects and many others may be produced by appropriately combining the crescendo and diminuendo cil'ects with each other and with the increasing and decreasing of intensities by the distinct scribed comprising, in combination, playing pneumatics; a main source of pneumatic power for operating said playing pneumatics; a regulator pneumatic having a valve interposed between said playing pneumatics and said mainsource of power; a pneumatic spring circuit acting upon said regulator pneumatic; and an automatically operating regulator valve in said pneumatic spring circuit.

2. An instrument of the character described comprising, in combination, playing pneumatics, a main source of pneumatic power for operating said playing pneumatics; a regulator pneumatic having a valve interposed between said playing pneumatics and the main source of power; a pneumatic spring circuit acting upon said regulator pneumatic and comprising a bleed to atmosphere and a bleed to exhaust; and an automatically operable means responsive to variations in exhaust in said pneumatic spring circuit, for relatively varying the capacities of said bleeds to maintain the degree of exhaust in said circuit substantially constant.

3. An instrument of the character described comprising, in combination, playing pneumatics, a main source of pneumatic power for operating said playing pneumatics; a regulator pneumatic having a valve interposed between said playing pneumatics and the main source of power; a pneumatic spring circuit acting upon said regulator pneumatic and comprising a bleed to atmosphere and a bleed to exhaust, a valve for varying the relative capacities of said bleeds, automatic-means responsive to variations in the degree of exhaust in said pneumatic circuit for operating said valve, and auxiliary means for varying the relative admission of exhaust and suction to said pneumatic spring circuit.

4. An instrument of the character described comprising, in combination, playing pneumatics, a main source of pneumatic power for operating said playing pneumatics; and a regulator interposed between said playing actions and the. main source of power, said regulator comprising a valve, a pneumatic open to regulated pressure and operatively connected to said valve, a pneumatic spring circuit acting upon and opposing the action of said regulator pneumatic and operatively connected to said valve, bleeds to atmosphere and exhaust, respectively, in said pneumatic spring circuit, automatic means for maintaining asubstantially uniform degree of exhaust in said pneumatic spring circuit, additional automatic means for increasing a desired degree of exhaust in said circuit when the same is reduced below a certain minimum; and automatic means connected to said additional means for continuing the operation thereof to increase for crescendo purposes the de gree of exhaust in said pneumatic spring circuit.

An instrument of the character .de scribed comprising, in combination, playing pneumatics, a main source of pneumatlc power for: operating said playing pneumatics; a valve interposed between the main source of power and said playing pneumatics; a regulating pneumatic operatively connected to said valve and arranged to receive regulated pressure; a pneumatic spring regulator circuit acting u on said valve in opposition to said regu ating pneumatic, said circuit having a bleed to atmosphere and a bleed to exhaust; automatic means responsive to variations in exhaust in said circuit, for maintaining uniform said degree of exhaust; and additional auxiliary automatic means responsive to variations in exhaust in said circuit for varying the relative admission of air to and exhaustof air from said circuit at different speeds.

6.'An instrument of the character described comprising, in combination, playing pneumatics, a main source of pneumatic power, for operating said playing pneu matics; a valve interposed between the main source of power and said playing pneumatics; a regulating pneumatic opera tively connected to said valve; a neumatie spring circuit acting upon said va ve in 0 position to said regulating pneumatic; bleeds to atmosphere'and exhaust for said pneumatic spring circuit; a valve for var ing the relative admission of air to and ex aust of air from said pneumatic spring circuit; op- I crating means for said last named valve operable in response to variations in the exhaust in said pneumatic spring circuit; a. tracker; and means for operating said valve from the-tracker. I i

, 7 An instrument of the character described'comprising, in combination, playing pneumatics, a main source of pneumatic power for operating said playing pneumatics a valve interposed between said main source of power and said playing pneumatics; a regulating pneumatic operatively connected to said valve; a pneumatic spring circuit actin upon said valve in opposition to said regu atinglpneumatic; bleeds to atmosphere and exhaust for said pneumatic spring circuit; a plurality of valves for varying at different speeds the relative admission of air to and exhaust of air from said pneumatic spring circuit; operating means forsaid valves responsiveto' different degrees of variation of exhaust in saidcir: cuit; a tracker; and means for operating said valves from the tracker to produce crescendo effects.

8. An instrument of the character described comprising, in combination, playing pneumatics, a mainv source of pneumatic haust in said circuit; a tracker; and means for operating said valves from the tracker.

9. An instrument of the character described comprising, in combination, playing pneumatics, a main source of pneumatic power for operating said playing pneumatics; a valve interposed between the main source of power and said playing pneumatics; a regulating pneumatic operatively connected to said valve; a pneumatic spring circuit acting upon said valve in opposition to said regulating pneumatic; bleeds to atmosphere and exhaust for said pneumatic circuit; a valve for varying the relative admission of air to and exhaust of air from said circuit; a diaphragm and chamberfifor operating said valve; a duct leading to said diaphragm chamber; a pneumatic in said pneumaticspring circuit and responsive to variations in suction therein; means operatedby said pneumatic for opening said duct to operate said diaphragm.

10. An instrument of the character described comprising, in combination, playing pneumatics, a main source of pneumatic power for operating said playing pneumatics; a valve interposed between the main source of power and said playing pneumatics; a regulating pneumatic operatively connected to said valve; a pneumatic spring circuit acting upon said valve in opposition to said regulating pneumatic; bleeds to atmosphere and exhaust for said pneumatic circuit; a valve for varying the relative admission of air to and exhaust of air from said circuit; a diaphragm and chamber for operating said valve; a duct leading to said diaphragm chamber; a pneumatic in said pneumatic spring circuit and responsive to variations in suction therein; means operated by said pneumatic for opening said duct tooperate said diaphragm; a tracker; and means connected to said tracker for open ing said duct to control said diaphragm.

11. An instrument of the character described comprising, in combination, playing pneumatics, a main source of pneumatic power for operating said playing pneumatics; a valve interposed between the main source of power and said playing pneumatics; a regulating pneumatic connected to said valve; a pneumatic spring circuit acting'upon said valve in opposition to said regulating pneumatic, said pneumatic spring circuit comprising an opening to atmosphere and an opening to exhaust and including a pneumatic responsive to variations in degree of exhaust in said circuit; a throttle valve between the opening to exhaust and the opening to atmosphere, and connections between said valve and sald pneumatic for operating the valve responsive to changes in.

exhaust in said circuit.

12. An instrument of the character described comprising, in combination, playing pneumatics, a main source of pneumatic power for operating said playing pneumatics; a valve interposed between the main source of power and said playing pneumatics; a regulating pneumatic connected to said valve; a pneumatic spring circuit acting upon said valve in opposition to said regulating pneumatic, said pneumatic spring circuit comprising an opening to atmosphere and an Opening to exhaust and including a pneumatic responsive to variations in degree of exhaust in said circuit, a, throttle valve between the opening to exhaust and the opening to atmosphere, connections between said valve and said pneumatic for operating the valve responsively to changes in exhaust in said circuit; and auxiliary means responsive to changes in exhaust in said circuit for varying the relative admission of air to and exhaust of air from said circuit.

'13. An instrument or" the character described comprising, in combination, playing neumatics, a main source of pneumatic power for operating said playing pneumatics, a valve interposed between the main source of power and said playing pneumatics; a. regulating pneumatic connected to said valve; a pneumatic spring circuit acting upon said valve in opposition to said regulating pneumatic, said pneumatic spring circuit comprising an opening to atmosphere and an opening to exhaust and including a pneumatic responsive to variations in degree of exhaust in said circuit, a throttle valve between the opening to exhaust and the opening to atmosphere, connections between said valve and said pneumatic for operating the valve responsive to changes in exhaust in said circuit; auxiliary means responsive to changes in exhaust in said circuit for varying the relative admission of air to and exhaust of air from said circuit; a tracker; and means operated from the tracker for operating said auxiliary means to produce crescendo eliects.

lit. An instrument of the character described comprising, in combination, pneumatic playing actions; a main source of pneumatic power for operating said playing actions; an expression controlling valve interposed between the main sourceoi pow-er and said playing actions; pneumatic means for governing said valve; a regulator valve responsive to variations and for governing the degree of exhaust within said pneumatic means to govern said expression valve; and

automatic means to control the saidregulator valve.

15. An instrument of the character described comprising, in combination, pneumatic playing actions; a main source of pneumatic power for operating said playing actions; an expression controlling valve interposed between the main source of power and said playing actions; pneumatic means for governing said valve; a regulator valve responsive to variations in and for governe ing the exhaust of said pneumatic means to govern said expression valve; and automatic variable-speed means for controlling said a regulator valve.

, 16. An instrument of the character described comprising, in combination, pneumatic playing actions; a main source of pneumatic power for operating said playing actions; an expression controlling valve interposed between the main source of power andsaid playing actions; pneumatlc means for governing said valve; a regulator valve responsive to variations and for governing.

the degree of exhaust within said pneumatic means to govern said expression valve; a

tracker; and means connected to the tracker for varying the normaloperation of thereg ulator valve.

17 An instrument of the character described comprising, in combination, pneu-v matic playing actions; a main source of pneumatic power for operating said playing actions; an expression controlling valve interposed between the main source of power and said playing actions; pneumatic means for governing said valve; a regulator valve responsiveto variations in and for governing the exhaust of said pneumatic means to govern said valve; a tracker; means. connected to the tracker for varying the normalv operation of the regulator valve; and further means connected to the tracker for varying the effective speed of operation of the vregulator valve.

18. An instrument otthe character described comprlsing, in combination, pneumatic play ng actions; a IIIZLHLSOUICG of pneumatic power for operatlng said playing actions; a valve interposed between the main;

pneumatics; and a regulator valve responsive matic-playingactions; amain source ofs pneumatic power for operating sa1d playingactions; an expression controlling valve interposed between the main source of power and said playing actions; a pneumatic operatively'connected to said expression valve for governing the same; a second pneumatic in communication with said other pneumatic; means for exhausting the connected to variation in and for automatically governing the exhaust of said connected pneu matics.

20. An instrument of the character described comprising, in combination, pneu matic playing actions a main source of pneumatic powerfor operating said playing actions; a valve interposed between the main I source-ofpower and saidplaying actions; a pneumatic operatively connected to said valve for governing the same; a second pneumatic in communication with said other pneumatic; means for exhausting the connected pneumatics; and automatic means operable by the movable boardof the second pneumatic for governing the exhaust of said connected neumatics.

21. An instrument of the character described comprising, in combination, pneumaticplaying actions; a main source of pneumatic. power for operating said playing actions; a valve interposed between the main source of power and said playing actions; a pneumatic operatively connected to said valve for. governing the same; a second pneu matic in communication with said other pneumatic; means for exhausting the connected pneumatics; a regulator valvefor governingithe exhaust of said pneumatics; a. diaphragm for the regulator valve; a duct to control the operation of the diaphragm; and means for automatically opening and closing said duct.

22. An instrument of the character describedmcomprising, in combination, pneus matic playing actions; a main source of pneumaticpower for o )erating said playing. actions; a valve interposed between the main source of power and said playing actions; a neumatic operatively connected to said va ve for governing the. same; a second pneumatic in communication with said other pneumatic; means for exhausting the connected pneumatics; a regulator valve for governing the-exhaust of said pneumatics; a diaphragm for the regulator valve; a duct to control the operation of the diaphragm; and duct opening and closing means operatively connected to the movable board of the second pneumatic,

23.'-An instrument of the character described comprising, in combination, pneumatic playing actions; a. main source of pneumatic power for operating said playing actions; an expression controlling valve in- 130 'nicati0n with said other pneumatics; means for exhausting the connected neumatics; a regulator valve for governing the exhaust of said pneumatics; a diaphragm for the regulator valve; a duct to control the oper- 1 ation of the diaphragm; a tracker; and duct opening and closing means operatively connected to the tracker.

'24. An instrument of the character described comprising, in combination, pneu matic playing actions; a main source of pneumatic power for operating said playing actions; an expression controlling valve interposedbetween the main source of power and said playing actions; a pneumatic operatively connected to said valve for governing'the same; a second pneumatic in communication with said other pneumatic; means for exhausting the connected pneumatics; a regulator valve for governing the exhaust of said pneumatics; a diaphragm for the regulator valve;'a duct to control the operation or the diaphragm; duct opening and closing means operatively connected to the movable board of the second pneumatic;

a tracker; and means to open and close said duct from the tracker.

25. 'An instrument of the character describedfcomprising, in combination pneumatic playing actions; a main source of pneumatic power for operating said playing actions; an expression controlling valve interposed between the main source of power and said playing actions; a pneumatic operatively connected to said valve for governing 1 the same a se'cond'pneumatic in communication with said other pneumatic; means for exhausting the connected pneumatics; a regulator'valve responsive to variation in and for automatically governing the exhaust 2 of said pneumatics; and further means for governing the speed of the exhaust of air from said pneumatics.

26. An instrument of the character described comprising, in combination, pneumatic playing actions; a main source of pneumatic power for operating said playing actions; an. expression controlling valve interposedbetween the main source of power and said-playing actions; a pneumatic operatively connected to said valve for governingv the same; a second pneumatic in communication with said other pneumatic; means for exhaustingthe connected pneumatics; a regulator valve for automatically governing the exhaust of said pneumatics; and further means operable from the movable board of the second pneumatic for automatically governing the speed of the exhaust of air from said Pneumatics.

27. Airinstrument of the chaacter deling said regulator valve.

scribed comprising, in combination, pneu matio playing actions; a main source of pneumatic power for operating said playing actions; an expression controlling valve interposed between the main source of power and said playing actions; a pneumatic operatively connected to said valve for governing the same; a second pneumatic in communication with said other pneumatic; means responsive to variations in and for exhausting the connected pneumatics a regulator valve responsive to variation in and for automatically governing the exhaust of said pneumatics; a tracker; and means operable from the tracker to govern the speed of admission of air to or exhaust of air from one of said pneuinatics by the regulator valve.

28. An instrument of the character described comprising, in combination, pneumatic playing actions; a main source of power for operating said playing actions; a throttle valve interposed between said main source of power and said pneumatic actions; a movable member connected to said valve for governing its throttling action; pneumatic expression overning means for vary ing expression by distinct increments, acting upon said movable member and tending to move the same in one direction; pneumatic means acting upon said movable member 95 and tending to move the same in an opposite direction; a regulator valve responsive to variation in and tor governing the exhaust of said last named pneumatic means; and automatic means to control the regulator 100 valve.

29. An instrument of the character described. comprising, in combination. pneumatic playing actions; a main source of power for operating said playing actions; a throttle valve interposed between said main source of power and said pneumatic actions; a movable member connected to said valve for governing its throttling action; pneumatic expression governing means for varying expression by distinct increments, acting upon said movable member and tending to move the same in one direction; pneumatic means acting upon said movable member and tending to move the same in an opposite direction; a regulator valve responsive to variation in and for governing the exhaust of said last named pneumatic means; and automatic variable speed means for control- 30. An instrument oi the charaflier described, comprising, in combination. pneumatic playing actions; a main source of power tor operating said playing actions: a throttle val we interposed between said main source of power and said pneumatic actions; a movable member connected to said valve for governing its throttling action: pneumatic expression governing means for verving expression by distinct increments, acting 1S0 upon said movable member and tending to move the same in one direction; pneumatic means acting upon said movable member and tending to move the same in an opposite direction; a regulator valve responsive to variation in and for governing the exhaust of said last named pneumatic means; a tracker; and means, connected to the tracker for varying the normal operation of the regulator valve.

31. An instrument of the character described, comprising, in combination, pneumatic playing actions; a main source of power for operating said playing actions; a throttle valve interposed between said main source of power and said pneumatic actions; a movable member connected to said valve for governing its throttling actions; pneumatic expression governing means for varying expression by distinct increments, acting upon said movable member and tending to move the same in one direction; pneumatic means acting upon said movable member and tending to move the same in an opposite direction; a regulator valve responsive to variation in and for governing the exhaust of said last named pneumatic means; a tracker; means connected to the tracker for varying the normal operation of the regulator valve; and further means connected to thetracker for varying the effective speed of operation of the regulator valve.

82. An instrument of the character described comprising, in combination, pneumatic playing actions; a main source of power for operating said playing actions; a throttle valve interposed between said main source of power and said pneumatic actions; a movable member connected to said valve for governing its throttling action; pneumatic expression governing means for varying expression by distinct increments, acting upon said movable member and tending to move the same in one direction; a pneumatic operatively connected to said movable member tending to move the same in an opposite direction; a second pneumatic in communication with said last named pneumatic; means for exhausting said connected pneumatics; and means responsive to variation in and for automatically governing the exhaust thereof.

An instrument of the character described comprising, in combination, pneumatic playing actions; a main source of power for operating said playing actions;

a throttle valve interposed between said main source of power and said pneumatic actions; a movable member connected to said valve for governing its throttling action; pneumatic expression governing means for varying expression by distinct increments, acting upon said movable member and tending to move the same in one direction; a pneumatic operatively connected to said movable member tending to move .the .samev in an opposite direction; a second pneumatic in communication with said last named pneumatic; means for exhausting the said connected neumatics; and a regulator valve responsive to variation in and for automatically governing the exhaust of said second matic expression governing means acting LlIJOIl-Sflld movable member and tending to move the same in one direction; a pneumaticoperatively connected to said movable member tendingto move the same in an opposite direction; a second penumatic in communication with said last named pneumatic; means for exhausting the said v neumatics; a regulator valve for automatically governing the exhaust of said second pneumatic; and a;

valve controlled by saidfisecond pneumatic for controlling in partthe. exhaust of said first pneumatic.

35. An instrument of the character described comprising, in combination, pneumatic playing actions; a main .source of power for operatingsaid playing actions; a throttle valve interposed between said main source of power and saidipneumatic actions; a movable \member connected to said valve for governing its throttling action; pneumatic expression governing means acting upon said movable memberand tending to move the same in one direction; a pneumatic operatively connected to said movable member tending to move the same in an opposite direction; a second pneumatic in communication with said last named pneumatic; a valve controlling communication therebetween and governed by said second pneumatic; and means providing a connection with a source of exhaust through said valve.

36. An instrument of the character described comprising, in combination, pneumatic playing actions; a main source of power for operating said playing actions; a throttle valve interposed between said main source of power and said pneumatic actions; a, movable member connected to said valve for governing its throttling action; pneumatic expression governing means acting upon said movable member and tending to move the same in one direction; a pneumatic operatively connected to said movable member tending to move the same in an opposite direction; a second pneumatic in communication with said last named pneumatic; and a valve governed by said second neumatic for alternatively connecting said rst pneumatic therewith or directly with a source of exhaust.

37. An instrument of the character described comprising, in combination, pneumatic playing actions; a main source of power for operating said playing actions; a throttle valve interposed between said main source of power and said pneumatic actions; a movable member connected to said valve for governing its throttling action; pneumatic expression governing means acting upon said movable member and tending to move the same in one direction; a pneumatic operatively connected to said movable member tending to move the same in an opposite direction; a second pneumatic in communication with said last named pneumatic; and a valve for disconnecting said pneumatics and placing said first pneumatic directly in communication with a source of exhaust.

38. An instrument of the character described, comprising, in combination, pneumatic playing actions; a main source of power for operating said playing actions; a throttle valve interposed between said main source of power and said pneumatic actions; a movable member connected to said valve for governing its throttling action; pneumatic expression governing means for varying expression by distinct increments, acting upon said movable member and tending to move the same in one direction; a pneumatic operatively connected to said movable member tending to move the same in an opposite direction; a second pneumatic in communication with said last named pneumatic; means for exhausting the connected pneumatics; and automatic means operable by the movable board of the second pneumatic for governing the exhaust of said pneumatics.

39. An instrument of the character described comprising, in combination, pneumatic playing actions; a main source of power for operating said playing actions; a throttle valve interposed between said main source of power and said pneumatidactions; a movablemember connected to said valve for governing its throttling action; pneumatic expression governing means for varying expression by distinct increments, acting upon said movable member and tending to move the same in one direction; a pneumatic operatively connected to said movable member tending to move theosame in an opposite direction; a second pneumatic in communi cation with said last named pneumatic; means for exhausting the connected pneumatics; a regulator valve for governing the exhaust of said pneumatics; a diaphragm for the regulator valve; a duct vto control the operation of the diaphragm; and means for automatically opening and closing said duct.

40. An instrument of the character described comprising, in combination, pneumatic playing actions; a main source of power for operating said playing actlons; a throttle valve interposed between said main source of power and said pneumatic actions; a movable member connected to said valve for governing its throttling action; pneumatic expression governing means for varying expression by distinct increments, acting upon said movable member and tend ing to move the same in one direction; a pneumatic operatively connected to said movable member tending to move the same in an opposite direction; a second pneumatic in communication with said last named pneumatic; means for exhausting the connected pneumatics; a regulator valve responsive to variation in and for automatically governing the exhaust of said pneumatics; and further means governing the speed of the exhaust of air from said pneumatics.

41. An instrument of the character described comprising, in combination, pneumatic playing actions; a main source of power for operating said playing actions; a throttle valve interposed between said main source of power and said pneumatic actions; a movable member connected to said valve for governing its throttling action; pneumatic expression governing means for varying expression by distinct increments, acting upon said movable member and tending to move the same in one direction; a pneumatic operatively connected to said movable member tending to move the same in an opposite direction; a second pneumatic in communication with said last named pneumatic; means for exhausting the connected pneumatics; a regulator valve for automatically governing the exhaust of said pneumatics; and further means operable from the movable board of the second pneumatic for automatically governing the speed of the exhaust of air from said pneumatics.

42. An instrument of the character described, comprising, in combination, pneumatic playing actions; a main source of power for operating said playing actions; a throttle valve interposed between said mam source of power and said pneumatics actlons; a movable member connected to said valve for governing its throttling action; pneumatic expression governing means for varying expression by distinct increments, acting upon said movable member and tending to move the same in one direction; pneumatic means acting upon said movable member and tending to move the same in an opposite direction; a regulator valve responsiveto variation in and for governing the exhaust of said last named pneumatic means; automatic means to control the regulator valve; a tracker; means operable from the tracker for governing the incremental expression varying means; and

Czi

other means operable from'the tracker for controlling the operation of the said regulator valve tor crescendo expression variations.

'43. An instrument of the character described comprising, in combination, pneumatic playing actions; a main source of power for operating said playing actions; a valve interposed between the main source of power and said actions; a pneumatic operatively connected to said valve for opening the same; a second pneumatic in communication with said other pneumatic means for regulating the pneumatic tension within said pneumatics; and further means for progressively collapsing the second, pneumatic for progressively increasing the pneumatic tension in the first pneumatic.

44. An instrument of the character. described comprising, in combination, playing pneumatics; a main source of power for operating said playing neumatics; a valve 0peratively interposed between said source of power and said playing pneumatics; means operatively connected to andtending to close said valve; a pneumatic operatively connected to and tending to open said valve; and means to maintain constant pressure within said pneumatic.

45. An instrument of the character described comprising, in combination, playing pneumatics; a main source of power for operating said playing pneumatics; a regulating valve interposed between said main source of power and said playing pneumatics; and means acting on said valve to regulate the air pressure on the playing pneumatic side of said valve comprising a pneumatic tending to close said valve, a pneumatic connected to said valve and acting to open said valve, and means to maintain constant the pressure in one of said pneumatics to thus' maintain constant the regulated pressure.

.46. An instrument of the character de scribed comprising, in combination, playing pneumatics: a main source of power for operating said player pneumatics: a valve in- -terposcd between the main source of power and said playing pneumatics; means operatively connected to and tending to close said valve; means operatively connected to and tending to open'said valve; including an air container having a movable wall operatively connected to said valve, and means to maintain a substantially.uniform degree of exhaust in said air container.

47. Expression -mechanism for an automatic musical instrument comprising, in coinbinationnn expression controlling valve pneumatically actuated means tending to move said valve in one direction; pneuniatically actuated means tending to move said valve in an opposite direction; means for'maintaining a substantially uniform degree of exhaust in one of said valve actuating means and means for progressively increasingor decreasing said degree of exhaust'for crescendo or diminuendo purposes.

4S. Expression mechanism for an automatic musical instrument comprising, in combination, an expression controlling valve pneumatic means tending to move the same in one direction; pneumatic means tending to move the same in an opposite direction; means to maintain a substantially uniform d'egree of exhaust in one of said pneumatic means; means to vary the area acted upon in the other said pneumatic means for expression changes of one character; and means to vary the degree of exhaust in the first said pneumatic means for expression changes of a different character.

.' 49gExpression mechanism' for an automatic musical instrument comprising, in combination, an expression controlling valve pneumatic means having a variable acting area; tending to move the valve in one direction; pneumatic means having a constant acting area and tending to move the valve in an opposite direction; means to vary the area acted upon in said first named pneumatic means for expression changes of one character, and means to maintain a normal substantially constant degree of exhaust in said other pneumatic means, the said last named means having also the capacity of varying said degree of exhaust for expression changes of another character.

50. An instrument of the character described comprising, in combinatiom playing pneumatics; a main source of power for operating said playing pneumatics, a valve interposed between the main source of power and. said playing pneumatics: a pneumatic .operat'vely connected to and tending to Certificate of Correction.

It is hereby certified that in Letters Patent No. 1,409,483, granted March 14, 1922,

upon the application of Guy Manly Russell, of Rochester, New York, for an improvement in Automatic Musical Instruments, errors appear in the printed specification requiring correction as follows: Page 5, line 87, after the Word source insert the Words of high exhaust pressure, and line 39, strike out the Words high exhaust pressure; and that the said Letters Patent should be read with these corrections therein that the same may conform to the record of the case in the Patent Ofiice.

Signed and sealed this 13th day of June, A. D, 1922.

[SEAL] KARL FENNING,

Acting Gammz'ssioner of Patents.

Certificate of Correction.

It is hereby certified that in Letters Patent No. 1,409,483, granted March 14:, 1922, upon the application of Guy Manly Russell, of Rochester, New York, for an improvement in Automatic Musical Instruments, errors appear in theprinted specification requiring correction as follows: Page 5, line 37, after the Word source insert the Words of high exhaust pressure, and line 89, strike out the Words high exhaust pressure; and that the said Letters Patent should be read with these corrections therein that the same may conform to the record of the case in the Patent Office.

Signed and sealed this 13th day of June, A. D., 1922.

[SEAL] KARL FENNING,

Acting Gammz'ssz'oner of Patents. 

